Re: [PATCH v2 2/2] platform/x86: intel_int0002_vgpio: Use acpi_register_wakeup_handler()

[Hans de Goede]

Hi,

On 4/3/20 3:25 PM, Rafael J. Wysocki wrote:
> On Fri, Apr 3, 2020 at 12:52 PM Hans de Goede <hdegoede@xxxxxxxxxx> wrote:
> > The Power Management Events (PMEs) the INT0002 driver listens for get
> > signalled by the Power Management Controller (PMC) using the same IRQ
> > as used for the ACPI SCI.
> >
> > Since commit fdde0ff8590b ("ACPI: PM: s2idle: Prevent spurious SCIs from
> > waking up the system") the SCI triggering, without there being a wakeup
> > cause recognized by the ACPI sleep code, will no longer wakeup the system.
> >
> > This breaks PMEs / wakeups signalled to the INT0002 driver, the system
> > never leaves the s2idle_loop() now.
> >
> > Use acpi_register_wakeup_handler() to register a function which checks
> > the GPE0a_STS register for a PME and trigger a wakeup when a PME has
> > been signalled.
> >
> > With this new mechanism the pm_wakeup_hard_event() call is no longer
> > necessary, so remove it and also remove the matching device_init_wakeup()
> > calls.
> >
> > Fixes: fdde0ff8590b ("ACPI: PM: s2idle: Prevent spurious SCIs from waking up the system")
> > Cc: 5.4+ <stable@xxxxxxxxxxxxxxx> # 5.4+
> > Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
> > ---
> > Changes in v2:
> > - Adjust for the wakeup-handler registration function being renamed to
> >    acpi_register_wakeup_handler()
> > ---
> >   drivers/platform/x86/intel_int0002_vgpio.c | 14 ++++++++++----
> >   1 file changed, 10 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/platform/x86/intel_int0002_vgpio.c b/drivers/platform/x86/intel_int0002_vgpio.c
> > index f14e2c5f9da5..9da19168b4f6 100644
> > --- a/drivers/platform/x86/intel_int0002_vgpio.c
> > +++ b/drivers/platform/x86/intel_int0002_vgpio.c
> > @@ -122,11 +122,17 @@ static irqreturn_t int0002_irq(int irq, void *data)
> >          generic_handle_irq(irq_find_mapping(chip->irq.domain,
> >                                              GPE0A_PME_B0_VIRT_GPIO_PIN));
> >
> > -       pm_wakeup_hard_event(chip->parent);
> > -
>
> If the event occurs before the "noirq" phase of suspending devices, it
> can be missed with this change AFAICS.
>
> >          return IRQ_HANDLED;
> >   }
> >
> > +static bool int0002_check_wake(void *data)
> > +{
> > +       u32 gpe_sts_reg;
> > +
> > +       gpe_sts_reg = inl(GPE0A_STS_PORT);
> > +       return (gpe_sts_reg & GPE0A_PME_B0_STS_BIT);
> > +}
> > +
> >   static struct irq_chip int0002_byt_irqchip = {
> >          .name                   = DRV_NAME,
> >          .irq_ack                = int0002_irq_ack,
> > @@ -220,13 +226,13 @@ static int int0002_probe(struct platform_device *pdev)
> >                  return ret;
> >          }
> >
> > -       device_init_wakeup(dev, true);
> > +       acpi_register_wakeup_handler(irq, int0002_check_wake, NULL);
>
> So I would just add the wakeup handler registration here.

Ok, will fix for the upcoming v3 of the series.

Regards,

Hans



> >          return 0;
> >   }
> >
> >   static int int0002_remove(struct platform_device *pdev)
> >   {
> > -       device_init_wakeup(&pdev->dev, false);
> > +       acpi_unregister_wakeup_handler(int0002_check_wake, NULL);
> >          return 0;
> >   }
> >
> > --